Underage Drinking in Latino Youth Abstract Alcohol use during adolescence is an important problem in the United States. Of particular interest are the alcohol use patterns of Latino populations and the development of alcohol abuse prevention strategies targeting Latino adolescents. The present research applies an integrated conceptual model to the analysis of Latino adolescent drinking in grades 7, 8 and 9. The model emphasizes traditional variables used to explain alcohol use in adolescence (e.g., behavioral intentions, expectancies, norms, self efficacy, affect, self image/concept, knowledge). In addition, the impact of variables directly tied to Latino culture will be studied (familismo, machismo, marianismo, acculturation, acculturation stress). Interviews will be conducted with approximately 700 (after attrition) adolescents and their mothers, twice each year for three years. The time span encompasses the transition from middle school to high school, a crucial period in adolescent development. Data will be collected from both mothers and adolescents. The research will elucidate the developmental dynamics of the emergence of under-age alcohol use in inner city, Latino populations representing Puerto Ricans and Dominicans living in the South Bronx of New York City. Structural equation modeling and growth curve modeling will be used to examine the relationship between Latino parenting, adolescent alcohol use and factors that impact such use with the transition to high school. The research analyzes adolescent alcohol use from an individual perspective, a family perspective and a cultural perspective, providing an integrated analysis across time. The research will lead to suggestions about the development of effective prevention strategies aimed at reducing alcohol use in underage Latino populations.